1. Field Of The Invention
This invention relates to race car wheels, and more particularly, to a multi-piece race car wheel having a center portion with an integrally formed hub thereon.
2. Description Of The Prior Art
In the field of automobile racing, a major consideration in the design of any portion of the racing vehicle, including the wheels, is to reduce weight while maintaining adequate strength to avoid failure during competition. Single piece, cast wheels of aluminum and magnesium alloys have been developed to provide a strong, relatively lightweight wheel. However, such cast structures necessarily require large cross-sectional thicknesses to meet strength requirements or casting process requirements, or both. Thus, while such wheels are made of lightweight material, they may not be as light as desirable because of the large thicknesses and the resulting increased material therein.
A lighter weight alternative to single piece cast wheels has been developed for race cars of the type generally referred to as "dirt track racers". Such vehicles are generally driven on relatively short, oval-shaped dirt tracks. During cornering in a race, the driver places the car into a controlled slide or "drift", literally sliding around the entire end of the oval track. Obviously, such cornering techniques place great stress on the wheel structure.
One prior art wheel includes two outer rim portions attached to a dished, centered piece. The centered piece is positioned adjacent to a separate hub which fits on the vehicle axle. On the opposite side of the dished center piece is a ring-like backup plate. The hub has a splined engagement with the axle. A knock-off cap holds the entire assembly in place on the axle.
This prior art wheel has an advantage in that the tire, rim portions and center piece may be detached from the hub while the hub is still on the vehicle in the event that the hub becomes jammed on the axle. This makes later removal of the hub easier because greater access to the hub is provided. However, a great disadvantage to this wheel is that the number of pieces necessarily increases the weight. In the highly competitive world of auto racing, reduced weight becomes a primary consideration over ease of repair or cost.
The race car wheel of the present invention solves this problem and provides a lighter weight wheel by using a single center portion which is attachable to outer rim portions. The center portion has a hub integrally formed therein and offset as necessary with respect to the rim portions.